function parseResponse(data) {
  var bookshelf = document.getElementById("bookshelf");
  
  for (var i=0; i<4; i++) {
    var cover = data.reader_books[i].book_edition.covers.cover_small;
    var title = data.reader_books[i].book_edition.title;
    var permalink = data.reader_books[i].permalink;
    
    var link = document.createElement("a");
    link.setAttribute("href",permalink);
    link.setAttribute("target","_blank");
    
    var img = document.createElement("img");
    img.setAttribute("src",cover);
    img.setAttribute("alt",title);
    if (i % 2 == 0) {
      img.setAttribute("class","odd");
    }
    
    link.appendChild(img);
    bookshelf.appendChild(link);
  }
}